Bird Technologies 6730B Series - Manual (Page 24)

Cleaning
Outside
Surfaces
The outside surface of these wattmeters should be wiped
free of dust and dirt when necessary. The principle main-
tenance required by the operator will be to periodically
wipe the accumulated dust and lint off of the radiator
fins. Excessive dust and lint on the cooling fins will inter-
fere with the efficient dissipation of heat. If the Teflon in-
sulator or metallic contact surfaces of the connector
should become dirty or grimy, wipe them off with a soft
cloth. Use a contact cleaner that is self-drying and
nonresidue-forming to clean the inaccessible internal
parts.
Radiator If any portions of the radiator are corroded or rusted,
clean the areas with a fine flint sandpaper, and then
touch them up with grey enamel.
Inspection
With the rugged and simple construction of the Termaline
Wattmeters inspection will only be necessary at six
month intervals. Check for coolant oil seepage around the
radiator tank, particularly at the front and back around
the underside of the clamping band. If leakage is
observed use the troubleshooting table and check the
tightness of the clamping screw and the fasteners around
the front cylinder.
Preventive Maintenance
Preventive maintenance is limited to cleaning the equip-
ment, particularly the radiator fins. It is important to
maintain the heat transfer efficiency of the cooling fins.
Also, occasionally check the coolant level in the radiator
tank.
RF Assembly Test
The electrical condition of the load resistor itself may be
ascertained generally from its dc resistance at room tem-
perature. It must be remembered that VSWR and RF im-
pedance are the prime requisites of a good dummy load,
however, occasionally checking the dc resistance will offer
an indication of a failing load.
Normally the dc resistance of the load will be a nominal
50 ohms. Stabilization of the resistive film or temperature
can cause a change in the dc resistance. Always check
Bird Model 6730B Series Termaline Wattmeter
16